1999 3500 cummins alarm issues
 

the alarm won't disarm,fob actually opens garage door. could door opener be interfering with alarm system?

Need more info. Factory or aftermarket alarm? Did this just start? What has changed? The more information you provide, the easier it is to offer assistance instead of us having to ask a ton of questions.

I think it is factory.Yes it just started,but something has been killing the batteries.Usually just charge them few minutes and it starts.Been taking key out of ignition and that seemed to end that. Seeing as the problem just started the only thing that has changed is that I pulled the truck in instead of backing it in like i usually do. This put the cab ant motor compartment directly under the opener motor where the bed always was. I was shocked when the garage door opened, and it doesn't always open but will with any of the 3 buttons on the fob at times.tried pulling all the relays under the hood to no avail. None of the owners manual ways to disarm work. Light on dash just keeps flashing,never even noticed it was there. I am second owner,just bought truck 2 months ago off of original owner,but he had cancer and has passed away so can't ask about it.